Resin flooring has become a standard in car parks in office buildings, shopping centres, public facilities, and multi-family residential buildings. In addition to being aesthetic and functional, these coatings play an important role in ensuring the structure’s durability. The requirements for these properties are set out in standards for concrete surface protection systems, floor underlays, and materials for their manufacturing.
Flooring refers to the top layer of a floor. The car park resin flooring is designed, among other things, to protect the concrete substrate on which it is laid from damage. Factors that typically occur in garages and car parks and which have a degrading effect on floor slabs include mechanical loads associated with intense vehicle traffic, moisture, temperature changes, rainwater, and de-icing salts brought in on tyres. The chloride ions contained in these salts are hazardous as, when they penetrate the reinforcement through cracks and fissures in the concrete together with water, they lead to its corrosion.
Resin flooring is used on car park surfaces to increase the durability of floor and ceiling slabs, which are structural elements of the building. These systems protect concrete surfaces, and their performance requirements can be found in the PN-EN 1504-2 standard. These include abrasion resistance, capillary absorption, water permeability, slip resistance and the ability to bridge substrate cracks. The standard also specifies the test methods to be used to determine these properties.
For example, the abrasion resistance of resin car park flooring should be tested in accordance with PN-EN ISO 5470-1. The result of the Taber test should show a mass loss of less than 3,000 mg when using a hard H22 abrasion wheel at 1,000 rpm and a load of 1,000 g. Using a soft CS-10 wheel would be incorrect. Test methods appropriate to PN-EN 13813 are also acceptable, for example, when the protective coating is intended for a floor that will be subject to significant mechanical loads.
Slip resistance, in the case of internal, damp surfaces, in accordance with PN-EN 13036-4, in the pendulum test, should correspond to class I, with a result of ≥ 40 units in the wet test, and in the case of external surfaces – class III, with a result of ≥ 55 units in the wet test.
Cracks in concrete car parks provide an entry point for chloride-containing water, so it is important that coatings are able to bridge them (tested according to PN-EN 1062-7). Designers should select the requirements for floors in relation to crack bridging (taking into account local conditions, including climate, crack width and change in opening) so that no damage occurs after testing for the appropriate class.
In construction practice, the two types of resin flooring most commonly used in car parks are epoxy and polyurethane. Both types of coating must comply with the requirements set out in the relevant Polish and European standards.
Polyurethane floors are more flexible than epoxy floors. This gives them a high ability to bridge cracks in concrete substrates with a lower system thickness than epoxy floors. Polyurethane-quartz garage flooring systems from the Deckshield group, designed for use in indoor car parks (Deckshield ID and Deckshield ID HD), in a test according to PN-EN 1062-7 at a temperature of -20oC, cover cracks in class A2 (crack width in the range of 0.25–0.5 mm). Systems intended for use on outdoor, uncovered surfaces (Deckshield ED and ED HD) bridge cracks in class A3 (crack width in the range of 0.5–1.25 mm).
Sometimes, when assessing and selecting flooring systems for multi-storey car parks, guidelines from other countries are also used, such as those issued by the German Reinforced Concrete Committee (DAfStb-Guideline, known as OS). These apply to all flooring layers, from the primer to the top layer, and the classification of the flooring depends on the thickness of the surface protection system. While this approach works well for epoxy floors, it overlooks the beneficial properties of flexible polyurethane systems. These systems meet the standard requirements, have exceptionally good crack-bridging properties and are more economical than OS systems with similar performance characteristics.
